• Summary
• Text account
• Data table and detailed info
• Distribution map
• Reference and further resources

Taxonomic source(s)
del Hoyo, J., Collar, N.J., Christie, D.A., Elliott, A., Fishpool, L.D.C., Boesman, P. and Kirwan, G.M. 2016. HBW and BirdLife International Illustrated Checklist of the Birds of the World. Volume 2: Passerines. Lynx Edicions and BirdLife International, Barcelona, Spain and Cambridge, UK.

Red List criteria met

Critically Endangered	Endangered	Vulnerable
-	-	-

Red List history

Year	Category	Criteria
2020	Near Threatened	D2
2016	Near Threatened	D2
2012	Near Threatened	D2
2008	Near Threatened	D2
2004	Near Threatened
2000	Lower Risk/Near Threatened
1994	Lower Risk/Near Threatened
1988	Threatened

Migratory status	not a migrant	Forest dependency	medium
Land-mass type		Average mass	8 g

	Estimate	Data quality
Extent of Occurrence (breeding/resident)	150 km2	medium
Severely fragmented?	no	-

	Estimate	Data quality	Derivation	Year of estimate
Population size	20000-49999 mature individuals	good	estimated	2019
Population trend	unknown	-	-	-
Generation length	2.24 years	-	-	-
Percentage of mature individuals in largest subpopulation	100%	-	-	-

Population justification: Partners in Flight (2019) estimated the population to number fewer than 50,000 mature individuals, thus it is placed in the band 20,000-49,999 mature individuals here.

Trend justification: The population trend is difficult to determine because of uncertainty over the impacts of habitat modification on population sizes. The population may now be increasing in southern Socorro following sheep and cat eradication efforts (J. E. Martínez-Gómez in litt. 2016); however, further evidence is required to confirm this increasing trend.

Country/Territory	Presence	Origin	Resident	Breeding visitor	Non-breeding visitor	Passage migrant
Mexico	extant	native	yes

Country/Territory	IBA Name
Mexico	Islas Revillagigedo

Habitat (level 1)	Habitat (level 2)	Importance	Occurrence
Forest	Subtropical/Tropical Dry	major	resident
Shrubland	Subtropical/Tropical Dry	major	resident
Altitude	0 - 1050 m	Occasional altitudinal limits

Threat (level 1)	Threat (level 2)	Impact and Stresses
Invasive and other problematic species, genes & diseases	Invasive non-native/alien species/diseases - Felis catus	Timing		Scope		Severity		Impact
		Ongoing		Majority (50-90%)		Unknown		Unknown
		Stresses Species mortality
Invasive and other problematic species, genes & diseases	Invasive non-native/alien species/diseases - Ovis aries	Timing		Scope		Severity		Impact
		Ongoing		Whole (>90%)		Slow, Significant Declines		Medium Impact: 7
		Stresses Ecosystem degradation

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Recommended citation
BirdLife International (2024) Species factsheet: Socorro Wren Troglodytes sissonii. Downloaded from https://datazone.birdlife.org/species/factsheet/socorro-wren-troglodytes-sissonii on 27/11/2024.
Recommended citation for factsheets for more than one species: BirdLife International (2024) IUCN Red List for birds. Downloaded from https://datazone.birdlife.org/species/search on 27/11/2024.